1. Field of the Invention
This invention relates to a display device, specifically to a display device that provides a first observation region with a first picture and provides a second observation region with a second picture.
2. Description of the Related Art
A liquid crystal display device using a liquid crystal panel for display (hereafter referred to as an LCD (Liquid Crystal Display)) has been known as a display device incorporated in a TV receiver, information equipment and the like. Relating to the display devices such as the liquid crystal display device, a dual picture display that provides a first observation region with a first picture and provides a second observation region with a second picture, has come to be known, as the information equipment diversifies in recent years.
A dual picture display device according to a conventional art will be described hereafter referring to the drawings. FIG. 12 is a cross-sectional view showing the display device according the conventional art. In the display device 100, there is disposed a display panel 10 that is made of first columns of pixels 10A that display the first picture and second columns of pixels 10B that display the second picture disposed alternately, as shown in FIG. 12. The first columns of pixels 10A and the second columns of pixels 10B are made of pixels each having a liquid crystal layer, for example. There is formed a so-called black matrix 11 between neighboring pixels in the first columns of pixels 10A and the second columns of pixels 10B. A light-shielding plate 50 made of metal or resin that has a light-shielding function is disposed above the display panel 10 through a transparent substrate (not shown) such as a glass substrate. The light-shielding plate 50 is provided with light-shielding portions 51 and openings 52 disposed alternately and extending parallel to the first columns of pixels 10A and the second columns of pixels 10B.
Next, how the structure described above works to realize the dual picture display will be explained. The first observation region A, which is located to the left of a position C directly above a center of the display panel 10, is provided with the first picture from the first columns of pixels 10A through openings 52 in the light-shielding plate 50, as shown in FIG. 12. At that time, the first observation region A is not provided with the second picture from the second columns of pixels 10B, because the light-shielding portions 51 in the light-shielding plate 50 block the second picture.
On the other hand, the second observation region B, which is located to the right of the position C directly above the center of the display panel 10, is provided with the second picture from the second columns of pixels 10B through the openings 52 in the light-shielding plate 50. At that time, the second observation region B is not provided with the first picture from the first columns of pixels 10A, because the light-shielding portions 51 in the light-shielding plate 50 block the first picture. As described above, there is performed the dual picture display in which the first observation region A is provided with the first picture and the second observation region B is provided with the second picture.
Technologies mentioned above are disclosed in Japanese Patent Application Publication No. 2005-258016.
With the dual picture display by the display device described above, however, there is caused a double image or an overlapping of the first and second pictures when the display panel 10 is observed from the position C directly above the center of the display panel 10 or its vicinity. That is, the first picture can not be distinguished from the second picture, thus a quality of the dual picture display has suffered.